Chainsaws

I purchased a Rancher 450 yesterday from Lowe's. They only had a display model in stock and I was in a hurry so I bought it with a 10% discount and they threw in a chain. I registered it online and then realized that if I would have bought oil or gas with it the warranty would have extended 2 more years. At this point, I haven't used the saw yet, would I be ahead to take it back and go to another Lowe's and
buy another (at full price) in order to get the additional 2 years?